Microwave-Assisted Green Synthesis of CQDs from Mesosphaerum suaveolens Extract: Photocatalytic Degradation and Anticancer Activity

In this study, Mesosphaerum suaveolens extracts were used for the green fabrication of fluorescent Carbon Quantum Dots (CQDs) by the microwave-assisted method. This study unravels the effect of CQDs on improving the photocatalytic degradation of methylene blue (MB) and Rhodamine B (RhB) dyes followed by the anticancer activity against human breast cancer cells (MDA-MB-231). The bio-fabricated CQDs indicated various characteristics that were analyzed, including phase, structure, functional groups, and binding energies. The CQDs displayed notable photocatalytic performance in the removal of MB (80.73%) and RhB (92.3%) dye, after 200 min of sunlight irradiation. The highest catalytic degradation activity of the CQDs is accredited to their high electron transport at the edges, which is helpful to the efficient separation of electron–hole pairs. Furthermore, the anticancer activity of CQDs was demonstrated against human breast cancer cells (MDA-MB-231). This research suggests that bio-fabricated CQDs act as active photocatalysts and hold promise as a potentially ideal material for mitigating water pollution and exploring anticancer potentials in the future. Graphical abstract